Try execute the following or put in into your .vimrc
vnoremap <C-r> "hy:%s/<C-r>h//gc<left><left><left>
By pressing ctrl+r in visual mode, you will be prompted to enter text to replace with. Press enter and then confirm each change you agree with y or decline with n.
This command will override your register h so you can choose other one (by changing h in the command above to another lower case letter) that you don’t use.